Table 1.

Summary of studies of vitamin status in patients with spine surgery

Ref.	Study design	Subjects	Significance
Schwalfenberg[6], 2009	Case series	6 patients with chronic back pain and failed back surgery	Repletion of inadequate vitamin D levels shows significant improvement or complete resolution of chronic low back pain symptoms
Pneumaticos et al[4], 2011	Case series	1 patient with osteoporosis with lumbar compression fracture	After kyphoplasty, vitamin D supplementation can improve muscle strength and decrease back pain
Waikakul[7], 2012	Retrospective study	9 patients with failed back surgery syndrome	Vitamin D supplementation can improve the functional scores of patients with failed back surgery syndrome
Zafeiris et al[5], 2012	Prospective longitudinal study	40 postmenopausal women with vertebral compression fractures	Patients with recurrent fractures have lower vitamin D levels than patients without recurrent fractures after kyphoplasty
Kim et al[9], 2012	Prospective study	31 female patients with lumbar spinal stenosis	Vitamin D deficiency is common in lumbar spinal stenosis patients and postoperative vitamin D is significantly correlated with surgical outcomes
Kim et al[11], 2013	Cross-sectional study	350 patients with lumbar spinal stenosis	Vitamin D deficiency is highly prevalent in lumbar spinal stenosis patients and is associated with severe pain
Stoker et al[10], 2013	Cross-sectional study	313 patients with degenerative spondylosis	There is a substantially high prevalence of hypovitaminosis D in patients undergoing spinal fusion
Stoker et al[19], 2013	Retrospective study	91 patients: 74 herniation, 17 no herniation	Vitamin D deficiency is associated with cervical disk herniation